Roll Forming Handbook / Edited by George T. Halmos

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10.1.4 Foundations, Foundation Bolts, and Leveling

Rollforming mills usually do not require aseparate foundation if the plant has areasonably good-qualit y,

6-in (150-mm) or thicker,reinforced concrete ﬂoor.Mechanical and pneumatic presses over 20 to 30

tons (180 to 270 kN) requireseparate foundation blocks in almost all cases (see Chapter 3). Hydraulic

presses usually do not need foundation blocks.

Uncoilers and most of the other equipment in the line do not requireseparate foundations. However,

all equipment needs foundation bolts to tie it to the ﬂoor after the line has been aligned.

The equipment manufacturer usually provides an accurate foundation bolt layout and either

recommends or supplies the right type and size foundation bolts.

Usually,the centerline of the mill servesasthe main datum line for the complete roll forming line.

Distances along the datum line and the hole locations perpendicular to that line are marked on the

drawings. The datum line position is marked on the ﬂoor with atig ht string.The hole locations are

transferredfrom the drawing and are marked on the ﬂoor.

To compensate for anypossible inaccuracies, providing areasonably large clearance around each pre-

installed foundation bolt is recommended (Figure10.3). This clearanceallows for slight bending of the

bolts to accommodatethe hole location on the equipment. Oncethe equipment is aligned and leveled

and the anchor bolts are tightened, the clearance around the bolts can be ﬁlled with concrete.

Forunits which are not heavy,the expandable type of anchor bolts can be used. After aligning and

marking the bolt holes on the ﬂoor,the lightweig ht unit can be moved sideways. Then, the marked holes

can be drilled and the expandable anchor plugs inserted. Next, the equipment should be placed back,

aligned, leveled again and the bolts tightened to ﬂoor.

All equipment is accurately leveled in both directions. Leveling is frequently accomplished with

leveling screws installed in the base of the equipment. Plates and shims are often positioned underneath

the base plates of presses to supportlarger surfaces. After being leveled at the ends, long units such as the

roll forming mill beds should also be leveled at their center to avoid sagging. Height adjustment is more

critical when the ends of two machine parts, such as the split mill beds, must be accurately positioned on

the same level. Uncoilers must be accurately leveled.

Washer

Plate

Grout

Filled after

installation

FIGURE 10.3 Clearance around foundation bolts allows adjustment.

Roll Forming Handbook10-4

10.1.5 Installing Roll Forming Mills

Line installation starts with positioning the rollforming mill. All other equipment is installed to suit the

mill. First, the mill is placed on the foundation bolts. If the dimensions of the hole locations on the

drawings and the lines transmitted to the ﬂoor are the same, then the center line of the roll space in

the mill should be exactly abovethe center line drawn on the ﬂoor.

If laser or optical alignment is not available, then using asimple plumb line should be sufﬁciently

accurate. Alignment starts by stretching asteel wire above the center line marked on the ﬂoor.The wire is

tightened between twosolid, nonmoving points outside the twoends of the roll forming line.

The location of the wire at each end can be rechecked with the plumb,just in case the anchor points of

the wire move.The best approach is to use two plumbs. If both plumbs are just at the marked center line

on the ﬂoor,then the wire above is exactly in the right position.

One sleeve placed on the ﬁrst top shaft and one on the last top shaft of the mill helps the alignment.

The sleeves have anotch or apoint marked exactly at the halfwaypoint of the roll space. For example, if

the roll spaceis24in. (60 mm), then the mark is exactly 12 in. (300 mm) on an approximately 13 in.

(330 mm) or longer sleeve. The sleeves are pushed against the shaft shoulders. The twoplumbs hanging

from the wire are positioned abovethese marks. The mill is moved sideways, back and forth until the tip

of each plumb is positioned exactly at the marks.

At this point, the mill has to be leveled in both directions and the center lines rechecked. When

everything is correct, the foundation bolts are tightened and the centering and leveling are checked again.

This completes the installation of the mill, which is the ﬁrst pieceofequipment in the line.

10.1.6 Aligning and Installing Uncoilers

The mandrel of the uncoiler must be perpendicular to the center line. In the case of tight lines

(lines without aloop between the mill and the uncoiler), the wider the strip,the more critical the

perpendicularity. If the uncoiler has asliding base, then its shoulder,against which the coils are loaded,

should be aligned withthe shaft shoulders. This means that the tip of the plumb,hanging at the center

line of the mill, should be at half roll spacedistancefrom the uncoiler backplate. If the uncoiler is not

adjustable in the direction of the mandrel axis, then the uncoiler backplate or stop is usually aligned

either withthe shaft shoulder (Figure 10.4)or, in asingle purpose mill, withthe entryposition of the

strip-edge into the rolls (Figure 10.5). This will assure that wheneveracoil is loaded onto the uncoiler

and is pushed against the backplate or stop,the lead end of the strip enters directly into the rolls.

However,ifthe roll set will be interchanged, then it is still better to align the shoulder of the uncoiler with

the shoulder of the mill shaft. Aspacer against which the coils are pushed can be installed in front of the

backplate. All coils pushed against the spacer will be aligned with the correct entryposition in the mill.

If optical or laser alignment is not available, then the perpendicularityofthe mandrel can be checked

easily witha8- to 16-ft (2- to 4-m) long rigid bar,ﬁrmly attached to the mandrel. The length of the bar

depends on how highthe wire is above the ﬂoor.The bar can be attached to the mandrel by clamps or

by tack welding.Anadjustable target attached to the far end of the bar should just touch the wire

(Figure10.6).

SHAFT

SHOULDER

COIL EDGE

BACK

PLATE

FIGURE 10.4 Uncoiler backplate is aligned with the shaft shoulders.

Equipment Installation, Roll Setup, Maintenance, and Troubleshooting 10-5

When, after about a90 8 rotation of the mandrel, the attachment on the bar touches the wire again (as

shown in Figure10.6), the mandrel is exactly perpendicular to the wire.If, after rotation, the bar is not

touching or pushing the wire,then the uncoiler is not perpendicular and the direction of the mandrel

must be slightly altered. After moving, the ﬁrst “touching” position has to be established again and the

mandrel has to be rotated. This procedureshould be repeated until the bar just touches the wire in both

positions, which means that the mandrel is perpendicular to the line.

The next step is to level the mandrel, then bolt the uncoiler (or its sliding base) to the ﬂoor.

It is highly recommended to install an additional “stop plate”with twotothree anchor bolts at one

corner of the uncoiler as shown in Figure10.7.This extra heavy stop plate or angle will reduce the chance

of loosing the perpendicularitywhen the mill “jerks”the uncoiler at everystart. This sudden pulling

action has the same effect as hammering, and after several hundreds and thousands of starts the mandrel

slowly movesand rotates in the direction of the mill (Figure10.8). This effect is noticeable in

approximately 30 to 40% of the installed uncoilers. Mandrel misalignment can create waviness and other

problems in the ﬁnished products.

COIL EDGE

ENTRY

GUIDE

ROLLS TRAP THE

EDGE OF THE COIL

BACK

PLATE

FIGURE 10.5 In asingle-purpose mill, the uncoiler backplate may be aligned with the strip edge trapped in the ﬁrst

pass rolls.

INCORRECT 2

INCORRECT 1

STARTING

POSITION

INCORRECT 1

CORRECT (90° )

MILL ALLIGNMENT WIRE

LINE ON THE FLOOR

FIGURE 10.6 Asimple method to align uncoiler mandrel90 8 to the centerline.

Roll Forming Handbook10-6

10.1.7 Aligning Presses

The centerline of the press must be directly above

the centerline marked on the ﬂoor.Unfortu-

nately,most press manufacturers do not mark

thefront-to-back centerline on thepresses.

Therefore, the centerline has to be measured

and marked at both the entryand exit ends of the

press. One or two simple templates (Figure 10.9)

protrudingfrom the press base can mark the

centerline and greatly simplify the alignment

with the wire and plumbs. Misaligned presses can

create problems, such as sections cut “off square,”

incorrect hole patterns, waviness, products stuck

in the cutoffdie, and so on.

When the press is aligned, it must be leveled

carefully in all directions and tied to the ﬂoor

with anchor bolts. If vibration pads are not used,

then the press is usually grouted (concrete placed

in the gap between the press base and the

foundation).

10.1.8 Aligning Other Equipment

in the Line

All other equipment in the roll forming line as

well as the conveyors and the transfer devices

havetobeproperly aligned, leveled, and fastened

to the ﬂoor or foundation.

10.1.9 Start-Up and Training

After anew line is installed and all service lines (electrical, air,etc.) are connected, the supplier usually

checks the installation and starts up the line. In most cases, the start-up commenceswiththe checking of

the alignment, the controls and the actions of each piece of equipment. Finally,material is fed through

the line and the operations are performed, at ﬁrst, if possible, at slow speed. When everything is

satisfactory, the line speed is increased to its maximum level. This procedureisbased on the assumption

that the line has already been tested and accepted at the supplier’splant.

In most cases, the operator and the supervisor havealready participated in the acceptancetest at the

supplier’splant and it is assumed that they are already familiar with the operation. However,the in-plant

training should be extended to other personnel including: supervisors, maintenancepersonnel and

FIGURE 10.8 Constant “jerking” of the strip can dislocate uncoiler from its original position.

STOP PLATE

MILL

FIGURE 10.7 One additional stop plate can prevent the

misalignment of an uncoiler.

Equipment Installation, Roll Setup, Maintenance, and Troubleshooting 10-7

additional mill operators. The functions normally carried out by the operators, such as: mill setup,line

operation, preparation and application of forming lubricants, daily lubrication of bearings, gears, and so

on, basic troubleshooting,and others should be partofthis training.

10.2 Roll Installation and Setup

10.2.1 Considerations for Roll Installation

Asingle set of rolls may contain 10 to 250 rolls and as manyspacers. All rollsand spacers havetobe

installed at the right place, usually with more than 0.001 in. (0.025 mm) accuracy.Each roll and spacer

must havethe right identiﬁcation and the operator must haveagood “setup chart” in ordertoplacethem

exactly at the right locations (see Section 5.16 to Section 5.18).

The following additional rules are applicable to most setups:

The pass numbers marked on the rollsand on the setup charts are usually not the same as the

stand numbers on the mill. For example, the rolls of Pass #4 are not necessarily installed on Stand

#4 (Figure 10.10).

Template

Center line

mark

Center line

Aligning Wire

Plumb

Template

FIGURE 10.9 An aligning template can simplifypress alignment with the mill centerline.

TO PRESS

STAND No.

10 987654321

654321

PASS No.

FROM UNCOILER

FIGURE 10.10 Last roll pass is installed in the last stand (in this case, Pass #6 is installed in Stand #10).

Roll Forming Handbook10-8

It is not unusual that suppliers decide to add additional pass(es) during the roll design and

manufacturing stage, or after the initial setup test. As aresult, some setup chartsmay show “0”

(zero)or“3A”and “3B,”or“3” and “3A”pass numbers (Figure10.11)instead of 1, 2, 3, 4, and

so on.

Side-rolls are sometimes assigned with apass number;for example, Pass #1, Pass #2, Pass #3, Pass

#4, Side-Roll Pass #5, Pass #6, and so on. This can mean that side-roll Pass #5 is mounted between

twostands, one holding Pass #4, and the other one #6 rolls(Figure10.12).

In some cases, side-roll stands are not numbered, or the side-roll Pass #5 mentioned above

is designated as Pass #4A and it is placed between Pass #4 and Pass #5. Because side-roll passes

are forming the sections, it is recommended that they are given asequential pass number

(as mentioned in the previous paragraph).

Regardlessofhow the rolls are numbered, the highest (last) pass number is placed on the last

stand, which is closest to the exit side of the mill.

TO PRESS

STAND No.

10 9876 54

321

43B3A3 21

PASS No.

FROM UNCOILER

FIGURE 10.11 Some suppliers mark the added or corrected passes as Pass #0 or Pass #3A, #3B and so on.

SIDE ROLL

PASS

SIDE ROLL

PASS

STAND No. 12 3456

PASS No.

12 344A 56

PASS No. 12 3456 7

TO PRESS

FROM UNCOILER

TO PRESS

FROM UNCOILER

FIGURE 10.12 Side-roll pass may haveits own pass number (like #5 in the upper drawing) or aletter designation

(like #4A in the lower drawing).

Equipment Installation, Roll Setup, Maintenance, and Troubleshooting 10-9

The method of marking the rolls is described in Chapter 5. The unwritten rule is that the ﬁrst

identiﬁcation number designates the pass number and the letter “T”or“B” stands for “top”or

“bottom”shafts. The next number denotes the sequence of rolls from the shaft shoulder.For

example, 3T4 means 3rd pass, top shaft, 4th roll from the driveside, and 12B8 represents 12th

pass, bottom shaft, 8th rollfrom the driveside.

It is an unwritten but widely accepted standard that on each shaft, the ﬁrst roll (Roll #1) or spacer

is installed ﬁrst and is pushed to the “drive”side, against the shaft shoulder.The last roll or spacer

shown on the setup chart(with the highest number) is closest to the operator.

Some suppliers include the spacers in the roll numbering system. This means that the ﬁrst

spacer located on the driveside is #1. Other suppliers incorrectly mark the drive-side spacer as

“IN” and the operator-side spacer as “OUT”orthey just mark the length of the spacer.

The very thin shims havenodesignated numbers and they are not marked. These shims are

identiﬁed by their thickness on the setup char t.

In the case of “multipurpose”rolls, the roll numbers (sequence) can be mixed up.These rolls must

be installed in the sequence shown on the setup charts (Figure10.13).

If aside-roll is made out of segments, these should be installed on the side-roll stand shaft

according to the rollsetup chart(Figure10.14).

10.2.2 Installing Rolls on the Shaft

The following procedures are applicable to conventional (standard) mills with shafts supported at both

ends. However,some of the principles are applicable to all types of roll forming mills.

Removethe left- and right-hand nuts from the top and bottom shafts.

Removethe bolts that fasten the outboardstands on the base.

Pull out the outboardstands and slide them sideways on the mill bed (if thereissufﬁcient space)

Check the shafts as described in Section 10.3.5 “Mill Maintenance.”Clean each shaft; pay special

attention to removing dirt, grit, and grease accumulated at the shoulder.

Lubricate the shafts lightly.

Both ﬂat faces of each roll and spacer must be wiped carefully to remove all dirtorgrit. All roll

markings should facethe operator unless otherwise stated on the setup chart. Most rollsare

marked in arecessed grooveonthe ﬂat surface facing the operator.However,rollmanufacturers

sometimes makethe mistake of marking the wrongfaceofthe rolls, or sometimes the rolls are for

multipurpose use. In these cases, marks may appear on both faces.

In most cases, the rolldiameters will dictate the sequence of roll installation between the top and

bottom rolls (Figure10.15).

If aroll is verythin (shor t), then it mayget stuck (wedged) on the shafts, unless it is pushed with

its faceexactly perpendicular to the shaft axis. The perpendicularityand ease of installation can

be achievedbypulling apreviously installed spacer or roll back against the side of the thin roll;

then both pieces can be pushed together until they are in the right position (Figure10.16).

Agood “clicking” sound usually indicates that the roll is fully pushed against the shoulder,ora

previously installed roll or spacer.

All rollsand spacers must be keyed to the shafts. Rolls without keys will rotate on the shaft and

will ruin its surface. Spacers without keys will also rotate and rub against the surface of the rolls.

Owing to constant movement, rubbing against the adjacentroll,their length will be reduced by

wear in ashortperiod of time. If the formed material has an abrasivesurface, then the spacer not

only gets shorter but it mayalso “cuts”into the rolls. Up to 0.100- to 0.150-in. (2.5- to 3.8-mm)

deep groovescan be worn into the hardened rolls by the scale which ﬂaked offfrom the hot

rolled steel.

Shims (if any) identiﬁed by their thickness should be installed at the location marked on the

setup chart.

Roll Forming Handbook10-10

FIGURE 10.13 Multipurpose rolls can be placed in different locations (not following numerical sequence) as shown

in the lower drawing.

DR3

OP3

OP2

OP1

DR2

DR1

FIGURE 10.14 Setup of segmented side-rolls follows the number sequence (OP [operator side], DR [drive side]

and #1 —install ﬁrst).

Equipment Installation, Roll Setup, Maintenance, and Troubleshooting 10-11

Installation of rollsusually starts at the last pass (closest to the press) by placing the ﬁrst top and

bottom spacers or rollsonthe shafts (check carefully the “T”or“B” marks on the rolls or

spacers).

When all the top and bottom rolls, spacers. and shims are on the shafts, push the outboardstand

back into position. (Watch yourﬁngers!)

Placeboth the top and bottom nuts on the shaft ends and tighten the bottom nut ﬁrst, then the

top nut.

Slide the outboardstand in and out until it is roughly in the middle of the long bearing sleeves

located in the bearing blocks of the stand.

Bolt the outboard stand to the mill base.

10.2.3 Checking Roll Gaps

Select asetup gage to suit the material thickness (maximum speciﬁed material thickness, including

“plus” thickness tolerance, coating,embossing,etc.).

Check the horizontal gaps with feeler gages on both the driveside and operator side of the proﬁle

(Figure 10.17). Setting screws should always be turned downwardsfor the ﬁnal adjustment of the

top shaft.

SEQUENCE OF

INSTALING ROLLS

SEQUENCE OF

INSTALING ROLLS

B1 B2 B3 B4

B5 B6

T1 T2 T3 T4

T5 T6 T7

45 81213

13 67 91011

FIGURE 10.15 Roll diameters dictate the sequence of roll installation.

231

FIGURE 10.16 Short, thin roll (#3) wedges easily on the shaft; it can be installed with the help of an already

installed, longer roll or spacer.

Roll Forming Handbook10-12

Check the nonhorizontal gaps (adjust as above, check shoulder alignment or shim if required).

However,checking the gaps withfeeler gage alone maynot be sufﬁcient (Figure10.18)evenifall

the rollsappear to be in the correct position.

Double check the gaps between rollswithamirror (Figure 10.19).

Check the thickness, width and other speciﬁcations of the material to be formed.

Enter (jog) the material through the mill, pass-by-pass.

Adjust set screws down if the roll gap is too big,and up if the pressure is too much (makethe last

adjustment always down)

Check the dimensions of the ﬁnished product.

Check deviation fromstraightness and ﬂatness.

Check the product surface.

Check again after rolling with lubrication applied (if lube was not used during setup).

Check other items on the mill (e.g., entr yguide). For setting straighteners, see Section 10.2.4.

Check other items on the line including: length measuring devicesorcounter setting, safety

devices, uncoilers, presses, and so on.

Runafew pieces at normal speed and check parts beforestarting production.

FIGURE 10.17 Checking gap with afeeler gage.

(a) (b) (c) (d)

FG FG

.003"

(0.075mm)

FEELER GAGES (FG)

FIGURE 10.18 After checking the gaps with feeler gages (a–c), the roll gap can still be incorrect, but it is better to

have“locked” rolls (d).

Equipment Installation, Roll Setup, Maintenance, and Troubleshooting 10-13